Please click at link below at the bottom of this page. When you get to Bob Diamond's website, check out "Whats New?". There is a cool news video there.
| BHRA Heartily Applauds This Initiative Here are some of the the praiseworthy aspects of this proposal: The $50 million price tag is certainly a very good price - cited to be 10% of the circa 1990's "Fred Papert" $500 million cost, quoted by the multinational construction consortium(s) he personally selected back then. The new plan must be avoiding utility relocation by not digging into the street more than a foot or so. That's another good idea. Aspects of this some this proposal that are of questionable practicality: These cars are too small (don't carry enough passengers to make the line close to profitable). Another problem we foresee is battery power itself: from an operational viewpoint, battery packs simply cant provide the instantaneous energy needed to make the cars accelerate fast enough to keep up with automobile traffic. Further, due to the principal of Conservation of Energy, it's impossible for any regenerative brake system to generate enough electricity to fully recharge the batteries on the car as it operates in service. There will always be power loss due to mechanical heat and friction (bearings, etc) and small electrical losses which add up quickly in a closed system. This is why battery cars were never used on main streetcar routes a hundred years ago. A battery is still only a battery. It needs recharging every few hours, and the car has to be removed from service. For example, you need many more fully charged spare battery cars to maintain the same 24 hour service as you would with a fleet of "standard" streetcars. This combined with the lower passenger capacity and poor acceleration led to the battery powered cars (yes they had them back then) being the first streetcars to be replaced by buses in the 1920's. BHRA's suggestions and comments on how to make this proposal even better: On the other hand, electrifying the proposed new route with a simple and reasonably visually unobtrusive "direct suspension" trolley wire (like the type used in Philadelphia and San Francisco), would only add about $5- $7 million to the project cost, and would greatly enhance the service and operating characteristics of the line: bigger, faster (but not too much heavier) streetcars take in more revenue per car operator, while being able to "keep up" with automobile traffic. No power substations or distribution is needed, as there are numerous opportunities to tap 600 volt DC power from the many subway lines along the trolley route. The MTA wouldn't even notice the power being used, its like adding one additional subway train to the overall system- with the power load of the individual streetcars spread over several subway lines. An interesting alternative "Green" approach, would be to retain the on- board battery technology, but combine it with a larger car body to carry more passengers, AND the direct suspension trolley wire to supply both additional battery "trickle charge" and "on demand" high energy input to the streetcars as required. The resulting "hybrid" power system would operate largely on battery energy derived from the regenerative braking on the streetcars, BUT the cars would have available the high instantaneous power needed for quick acceleration that can only be provided by an overhead trolley wire. Further, the trolley wire would supply the extra "trickle charge" needed to over come the "loss due to friction" inherent in any regenerative brake power feedback system...In other words, the streetcars would never need to be removed from service in order to recharge their batteries, and only a minimal amount of "outside" electrical energy would be needed to be drawn from the overhead wire at any given time. A truly "Green" urban mass transit vehicle :-) Compare to the energy wasting and greenhouse gas spewing buses currently in use (including the "Hybrid CNG- Electric" models), which on a "good day", have a fuel efficiency of less than 3 miles per gallon, and on a "bad day" get less than 1 mpg (CNG Therm equivalent). The novel idea of using custom built car bodies honoring the original trolleys of the 3rd Avenue Railway could still be used. New Orleans RTA still builds brand new streetcars in the "Perley Thomas" 1920s style that matches their vintage fleets (but have A/C, are ADA accessible and have modern propulsion systems). Other private companies in the US also build old-style replica streetcars with modern amenities. Another idea is to run modern US built streetcars and also run vintage trolleys mixed in with modern streetcars (some European cities such as Lisbon, Portugal do this), Tuscon, Az also intends to do this on their under construction streetcar system. One more imaginative idea would be something similar to the old "AFX" slot cars of our youth: a single common electric power chassis with many interchangeable car bodies that could be "snapped on". | ||||
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